Crude oil is a complex mixture of hydrocarbons (e.g. paraffins, aromatics, napthenes), sulphur compounds (e.g. sulphur,
sulphides), amines, metals (e.g. Ni, Fe) and salts (e.g. NaCl, sand). Quantitative chemical analysis of such combinations
is difficult and requires partial or complete separation of the components, challenging outside of the laboratory.
Qualitative chemical analysis of oil is simpler using techniques such fluorescence spectroscopy. In this paper we will
present fluorescence (spectra and lifetime) data for crude oil samples of varying (specific) API gravity and show how
qualitative chemical information can be extracted from the spectra. This will include data obtained using synchronous
scanning fluorescence spectrometry (SS) and time-resolved emission spectroscopy (TRES) and demonstrate the ability
of utilising these methods to obtain better qualitative chemical information and hence the ability to "fingerprint" crude
oil.
The use of insulation within the oil and gas industry to provide heat retention during production downtime is important
to reduce the risk of hydrate formation within the flow-loops in the subsea infrastructure. Hydrate formation can
significantly decrease the production efficiency and hence the profitability of the well. Hydrates can also introduce
serious safety risks, if formed with in critical components such as safety valves. During production downtime the
elevated temperature of equipment such as XTs will begin to equalize to the ambient subsea temperature. The accurate
assessment of the effectiveness of such insulation is thus critical. Monitoring insulation performance during cool down
trials is typically performed during test and assembly of production equipment using a limited number of electrical
sensors. The use of multiplexed fibre optic sensors offers a reduction in the number of penetrations in the insulation,
when compared to traditional electrical sensors and thus allows far more representative temperature measurements to be
made. Additionally, conventional electrical sensors will rapidly degrade in the subsea environment, making them
unsuited for long term subsea monitoring.
In this paper we report the use of embedded optical fibre sensors, which should maintain their full performance over the
lifetime of the subsea equipment. This would enable the long term insulation performance to be assessed after a tree is
recovered for maintenance, or even allow continuous monitoring of the insulation performance during service. Results of
tests carried out in an environmental chamber to show the performance of the sensors during cooling cycles are reported
and initial results taken during production testing prior to deployment of the equipment subsea are reported.
KEYWORDS: Lead, Profiling, Cameras, Laser systems engineering, Data modeling, 3D modeling, Imaging systems, Distance measurement, 3D metrology, Scanners
The correct alignment and setting of the components inside subsea wellheads is critical to ensure that all seals perform at
the high pressures found in subsea hydrocarbon production systems. Of particular importance is the alignment of the
tubing hanger and how it engages with the subsea trees or wellhead. The tubing hanger supports the production tubing
string with carries the hydrocarbon from the reservoir and experiences pressures up to 15 kPsi. Full and correct
engagement of the locking and sealing mechanisms of the tubing hanger is critical in containing the production fluids.
Here we present the results of a trial of a laser profiler to assess the interior surfaces of a wellhead. The scanner has been
shown to be capable of effectively inspecting the interior surface of the wellhead for damage and measuring the interior
structures to allow the tubing hanger to be installed correctly.
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